Parking - Sweden - Göteborg (Gothenburg)

We are travelling by car to Göteborg in July. We will arrive on Saturday afternoon and leave early on Monday. We will stay on Mölndalsvägen.

What are general parking rules in Sweden? Can we park on the street on Sundays for free? Are there any parking spaces where we can leave the car for the whole period? How much will it cost? Is the system in the downtown like you have to pay to park on the street in the daytime on Monday-Saturday and the rest of the time it's free?

As we will be staying in the center, we don't want to part the car too far from the hotel.

I know that with Göteborg city card you can park for free, but if parking on Sundays is free, I do not see any point in buying this card.